NDH shuttles electrons from NAD(P)H:plastoquinone, via FMN and iron-sulfur (Fe-S) centers, to quinones in the photosynthetic chain and possibly in a chloroplast respiratory chain. The immediate electron acceptor for the enzyme in this species is believed to be plastoquinone. Couples the redox reaction to proton translocation, and thus conserves the redox energy in a proton gradient.

else case <OC:Cyanobacteria>

Function

NDH-1 shuttles electrons from an unknown electron donor, via FMN and iron-sulfur (Fe-S) centers, to quinones in the respiratory and/or the photosynthetic chain. The immediate electron acceptor for the enzyme in this species is believed to be plastoquinone. Couples the redox reaction to proton translocation, and thus conserves the redox energy in a proton gradient.

else case <OC:Methanomicrobia>

Function

FPO shuttles electrons from F(420)H(2), via FAD and iron-sulfur (Fe-S) centers, to quinones in the F(420)H(2):heterodisulfide oxidoreduction chain. The immediate electron acceptor for the enzyme in this species is believed to be methanophenazine. Couples the redox reaction to proton translocation (for every two electrons transferred, 0.9 hydrogen ions are translocated across the cytoplasmic membrane), and thus conserves the redox energy in a proton gradient.

else case <OC:Mycobacterium> or <OC:Rhodothermus>

Function

NDH-1 shuttles electrons from NADH, via FMN and iron-sulfur (Fe-S) centers, to quinones in the respiratory chain. The immediate electron acceptor for the enzyme in this species is believed to be menaquinone. Couples the redox reaction to proton translocation (for every two electrons transferred, four hydrogen ions are translocated across the cytoplasmic membrane), and thus conserves the redox energy in a proton gradient.

else

Function

NDH-1 shuttles electrons from NADH, via FMN and iron-sulfur (Fe-S) centers, to quinones in the respiratory chain. The immediate electron acceptor for the enzyme in this species is believed to be ubiquinone. Couples the redox reaction to proton translocation (for every two electrons transferred, four hydrogen ions are translocated across the cytoplasmic membrane), and thus conserves the redox energy in a proton gradient. This subunit may bind ubiquinone.

end case

case <OG:Chloroplast> or <OC:Cyanobacteria>

Catalytic activity

NAD(P)H + plastoquinone = NAD(P)(+) + plastoquinol.

else case <OC:Bacteria> and not <OC:Cyanobacteria>

Catalytic activity

NADH + a quinone = NAD(+) + a quinol.

end case

case <OG:Chloroplast>

Subunit

NDH is composed of at least 16 different subunits, 5 of which are encoded in the nucleus.